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1.
New findings are given for the Astragalus sect. Incani , which occurs within the area covered by the Flora of Iran. Astragalus wojciechowskianus Ranjbar is described as a new species. A. procerus Boiss. & Hausskn . , A. cottonianus Aitch. & Baker, A. achundovii Grossh., A. orduabadensis Grossh. and A. glaucophyllus Bunge are reported as new records for the flora of Iran .   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 443–447.  相似文献   

2.
Astragalus neo-assadianus (Fabaceae), a new species endemic to Iran, is described and illustrated. This species belongs to A. sect . Alopecuroidei and is distinct and interesting among the Iranian species. It is confined to the north-eastern part of Iran (Khorasan Province) and only known from a single collection close to the Turkmenistan frontier.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 197–200.  相似文献   

3.
Flower and fruit specimens of 184 individuals were sampled to investigate patterns of intraspecific variation and to evaluate recognition of taxa within the Acer tschonoskii complex using morphometric analysis. Previous taxonomic treatments have considered A. tschonoskii var. rubripes (=  A. komarovii ) and A. tschonoskii var. tschonoskii to be separate species. The morphological discontinuity between these two taxa was evident in peduncle and pedicel length, and in number of flowers. In addition, the delimitations of some species within sect. Macrantha were clarified using these diagnostic characters. In view of the geographical distribution of the A. tschonoskii complex, which includes many taxa of sect. Macrantha from China to Japan through Korea, the long raceme with many flowers ( A. sikkimense ) and unlobed leaf are considered more primitive than the short raceme with a small number of flowers and five-lobed leaf ( A. maximowiczii and A. komarovii ). However, many intermediate taxa were present. This study also suggests that several Chinese taxa, such as A. metcalfii, A. taronense, A. hookeri and A. grosseri , may be subject to different taxonomic interpretation and should be reinvestigated morphologically.  © 2003 The Linnean Society of London. Botanical Journal of the Linnean Society, 2003, 143 , 29−42.  相似文献   

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Naturally shed hairs are an important source of genetic material for both conservation and forensics but are notoriously poor sources of DNA. DNA degradation in hair roots is caused by apoptosis as part of the cycle of hair growth and by autolysis in decomposing animals. Shed hairs are additionally exposed to degenerative environmental processes. However, genetic studies rarely examine hair root morphologies or refer to root growth phases prior to analysis, and detailed knowledge of the rapidity of DNA degradation amongst shed hairs is lacking. We examined the effects of biological and environmental processes on western lowland gorilla ( Gorilla gorilla gorilla Savage and Wyman) hair roots with respect to morphological characteristics and polymerase chain reaction (PCR) success at eight nuclear loci. Root type frequencies indicate that gorilla body hairs may exhibit a longer telogen phase than human head hairs. All plucked hair root types amplified more efficiently than shed hairs, and only 41% of shed hairs had root types considered suitable for genotyping. Telogen hairs from fresh nests were four-fold more useful for genotyping if the roots were associated with translucent epithelial tissue, and preselection of these root types doubled the overall data-yield to 58%. Nest age correlated with root morphology and PCR success, and PCR success was almost halved after 3 days of exposure. Finally, an association between postmortem interval, root morphology, and PCR success was observed that was consistent with postmortem changes reported in human head hairs.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 281–294.  相似文献   

7.
Multivariate analysis of leaf radian measurements was used to investigate variation in leaf shape among 34 Asian species of the Uvaria group, a large palaeotropical group of climbing Annonaceae characterized by imbricate petals and stellate hairs. Raw data were normalized by conversion into 15 ratio characters and using the log10 transformation. All species surveyed showed a unique leaf-shape 'bauplan'. The ratio character with the greatest discriminating power in both the Principal Components Analysis and Discriminant Analysis (DA) results was a measure of the shape of the leaf base. Ratio characters with the highest factor loadings for principal components 1 and 2 clearly separated the sampled taxa when plotted against one another and provided support for the retention of several taxa as distinct species or varieties. Classification of cases into taxa using DA yielded a correct classification rate of only 52% for the ratio-transformed data; however, division of taxa in the dataset into smaller subgroups defined by discrete morphological characters significantly increased the accuracy of case identification to between 67 and 100% of cases correctly classified, depending on the group. Case identification using DA on log10-transformed data was higher than for the ratio values in the entire dataset (61.7%) and the larger subgroups. However, the rate of correct case assignment was lower in the smaller groups than for the ratio data.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 231–242.  相似文献   

8.
Seeds of 101 species from 14 genera were observed using stereoscopic and scanning electron microscopy. Sclerotesta morphology is stable within the genera of Magnoliaceae. Two different morphological types are described according to features of the chalazal region, which have great value in classification and have been found only in Magnoliaceae. One is the pore type, characterized by being simple, observed in the relatively primitive taxa of this family, including Manglietia, Pachylarnax, Magnolia (19 species), Aromadendron, Talauma (eight species), Parakmeria (one species), Kmeria (one species), Elmerrillia and Liriodendron . The other one is the tube type, which is characterized by having a more complex structure consisting of a central hollow tube contained within a hole. This type was observed in relatively advanced taxa, including Manglietiastrum, Magnolia (15 species), Talauma (three species), Parakmeria (four species), Kmeria (one species), Alcimandra, Michelia, Paramichelia and Tsoongiodendron . Transitional types between these two were observed in some species of Magnolia . Chalazal region morphology, together with other useful sclerotesta characters, including seed size, shape, the raphal sinus and the external surface of the sclerotesta, may be used as diagnostic characteristics of genera, and even species in Magnoliaceae. A key to identify the different genera is supplied.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 407–424.  相似文献   

9.
Swertia barunensis P. Chassot sp. nov. from Nepal is described and illustrated. It was collected in 1997 in an alpine meadow in the Makalu Barun National Park at an elevation of 4200 m. It belongs to Swertia section Macranthos T.-N. Ho & S.-W. Liu and resembles S. pseudohookeri H. Smith, from which it differs mainly by the shape of the nectary and the exomorphic seed structure. A key to all the species of sect. Macranthos is provided. The affinities of S. barunensis with some other taxa in the subtribe Swertiinae (Griseb.) Rchb. are also briefly discussed.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141, 389–394.  相似文献   

10.
Pseudopollen is found on the labella of several species of Maxillaria and is formed by the fragmentation of uniseriate, multicellular, moniliform trichomes. The resultant component cells are rich in protein. Since flowers of pseudopollen-forming species generally lack nectar, it is probable that pseudopollen gradually replaced nectar as the pollinator reward. However, direct evidence for this hypothesis is lacking. The present paper examines the labellar micromorphology of five Brazilian species of Maxillaria assigned to the M. discolor alliance. The flowers of two of these species, namely M. violaceopunctata and M. villosa , produce both food hairs and a lipoidal, labellar secretion which is rich in aromatic amino acids. Moreover, in the case of M. violaceopunctata , the secretion was found to contain reducing sugars. This may represent an intermediate stage in the transition from nectar-producing to pseudopollen-forming flowers. SEM studies indicate how pseudopollen-forming, moniliform trichomes, such as those found in the Maxillaria grandiflora complex, may have evolved from simple, uniseriate, multicellular hairs.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 143 , 151−158.  相似文献   

11.
Several Central American species of Piper sect. Macrostachys have obligate associations with ants, in which the ant partner derives food and shelter from modified plant structures and, in turn, protects the plant against fungal infection and herbivory. In addition to these obligate ant-plants (i.e. myrmecophytes), several other species in Piper have resident ants only sometimes (facultative), and still other plant species never have resident ants. Sheathing petioles of sect. Macrostachys form the domatia in which ants nest. Myrmecophytes in sect. Macrostachys have tightly closed petiole sheaths with bases that clasp the stem. These sheathing petioles appear to be the single most important plant character in the association between ants and species of sect. Macrostachys . We examined the structure and variation of petioles in these species, and our results indicate that minor modifications in a small number of petiolar characters make the difference between petioles that are suitable for habitation by ants and those that are not.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 181–191.  相似文献   

12.
The corollas of three species of Onoseris , 13 species of Trichocline and one species of Uechtritzia (Asteraceae, Mutisieae) exhibit trichomes that are morphologically similar to the twin hairs which are traditionally considered exclusive of the cypselas in Asteraceae. Four types of trichomes were found: 1-celled, 2-celled, 3-celled, and 4-celled. The 3-celled and 4-celled corolla hairs are those which most resemble the typical cypsela twin hairs. The ontogeny of the corolla hairs was analysed and coincidences with the ontogeny of the cypsela twin hairs were found. (1) An anticlinal division of the epidermal mother cell originates two hair cells which, in turn, originate the basal cells (sometimes one of them is reduced or similar to the epidermal cells) by oblique or periclinal subdivision. (2) In some cases the basal cell(s) of the 3- or 4-celled corolla hair elongates and reaches the same length as the hair cells. The same kind of trichomes have been demonstrated in cypselas of Mutisieae. (3) The 1- and 2-celled corolla hairs have already been described as variants of the cypsela twin hairs. Based on this evidence we conclude that the corolla hairs of Onoseris , Trichocline and Uechtritzia are twin hairs. It is hypothesized that the 1–4 corolla hairs could be involved in water absorption, as occurs in the cypsela twin hairs.  © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 427–433.  相似文献   

13.
Until recently, all papillated specimens of Pareledone were ascribed to the species Pareledone charcoti (Joubin, 1905), of which P. aurorae (Berry, 1917) was considered a junior synonym. Re-examination of the papillated type material of Pareledone, coupled with extensive fishing over several years off the Antarctic Peninsula, has led to a revision of this position. Seven new species of papillated Pareledone are identified from the Antarctic Peninsula region. They are identified by subtle taxonomic characters, such as the morphology and placement of their papillae, although traditional indices often fail to separate the species. Whilst apparently sympatric, there is some evidence of niche separation of these species with respect to depth. A key is provided for their identification.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 75−108.  相似文献   

14.
A new species, Psephellus turcicus A.Duran & Hamzaoğlu (Asteraceae) in sect. Psephelloidei (Boiss.) Wagenitz & Hellwig is described and illustrated from Anatolia, Turkey. The species grows on limestone crevices in Kazankaya Canyon (A5 Yozgat) in central Anatolia. A neo-endemic confined to Kazankaya Canyon, it is closely related to Psephellus psephelloides (Freny & Sint.) Wagenitz. Diagnostic morphological characters from closely similar taxa are discussed, and arranged in a key of Turkish similar Psephellus Cass. The ecology, biogeography and conservation status of the species are also presented. Achene surface morphology of P. turcicus and P. psephelloides are examined by SEM. The geographical distribution of the new species and other related species is mapped.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 495–500.  相似文献   

15.
A new species of Veronica vadiniense in section Veronica is described from material from the Cantabrian Range, in the north-east of the province of León (north-west Spain). Several morphological characters related to stems, leaves, racemes, flowers and capsules are given, and also those related to the indumentum of different parts of the plant, especially calyx lobes and capsule. Indications about distribution and habitat with reference to bioclimatic, biogeographical and phytosociological aspects are provided. Diagnostic features are also given to enable comparison with the most similar species, Veronica officinalis and V. allionii , particularly in the indumentum and consistency of leaves, and in the indumentum and shape of the capsule.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 119–124.  相似文献   

16.
Karyological information on Iberian Ophrys species is very limited. This paper provides the haploid and diploid chromosome numbers of 11 taxa of sect. Pseudophrys and sect. Ophrys , both of which are well represented in the Iberian Peninsula, and two taxa from Tunisia. The first data on chromosome numbers for O. vasconica (2 n  = 72, 74), O. ficalhoana (2 n  = 36), O. picta (2 n  = 36), O. sphegifera ( n  = 18, 2 n  = 36, 38) and O. passionis (2 n  = 36) are also presented, confirming the stability of the chromosome number in Ophrys . In addition, populations of the group O. omegaifera ( O. dyris and O. vasconica ), together with tetraploidy, pentaploidy and the existence of aneuploid phenomena, are reported for the first time in Iberia. The basic diploid number is always 2 n  = 36. The karyotypes of several species were analysed. Evolutionary trends in Ophrys chromosomes are discussed. Taxonomic and phytogeographical details are provided on several species or groups of species from Iberia.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003 , 142 , 395−406.  相似文献   

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18.
Claoxylon and Micrococca are the only Euphorbiaceae genera that have rough dried leaves (fresh ones are smooth) because of protruding styloid (needle-like) crystals more or less perpendicular to the leaf surface, which perforate the epidermis and cuticle. A broad leaf anatomical study of the subtribes Claoxylinae, the monogeneric Lobaniliinae, and Mercurialis of the Mercurialinae (95 of a possible 235 species in all six genera) showed that styloids are present in Claoxylon , Discoclaoxylon , Erythrococca , Lobanilia , and Micrococca , and lacking in Claoxylopsis and Mercurialis . Contrary to Claoxylon , the dried leaves of Discoclaoxylon , Erythrococca , Lobanilia , and Micrococca are not rough, because the styloids do not perforate the epidermis during drying and therefore herbarium leaves generally remain smooth. The presence of styloids supports a clade in a recent molecular phylogenetic study that unites subtribes Claoxylinae and Lobaniliinae as Claoxylinae s.l. Mercurialis (no styloids) is sister to all other taxa (with styloids) in the monophyletic Claoxylinae s.l. The styloids form a synapomorphy for a monophyletic part of the Claoxylinae ( Claoxylon , Discoclaoxylon , Erythrococca , Lobanilia , and Micrococca ). Other leaf anatomical notes are provided, together with an overview of the occurrence of styloids, stomata, and druse crystals for most species in the Claoxylinae. The indumentum ranges from (virtually) absent to a sparse or dense tomentum of straight and thick- or thin-walled unicellular hairs (most common), curly hairs, or two-armed hairs ('Malpighiaceous hairs'). The last two hair types probably form diagnostic characters for species groups within the genus Claoxylon .  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 445–457.  相似文献   

19.
A new species, Acantholimon evrenii sp. nov. is described and illustrated for the first time in sect. Glumaria from Turkey. The species is confined to B7 Elazığ in East Anatolia where it grows on rocky mountain steppes. The diagnostic morphological characters from closely related species are given, along with a discussion dealing with its taxonomic relationship. Its conservation status is indicated. A revised key is also provided for the Acantholimon species with heterophyllous leaves, two or more flowered and four or more bracteated spikelets.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 351–356.  相似文献   

20.
The degree of sexual seed set and the ability to cross were investigated in three taxa of Potentilla section Niveae ( P. chamissonis , P. insularis and P. nivea ) from the Svalbard Archipelago. Emasculated and bagged flowers had little or no seed set, while 71% of the emasculated, bagged and pollinated flowers had some. The taxa are interpreted as pseudogamous apomicts. Parental plants and offspring were subjected to isozyme analysis. Most of the offspring were clones of the mother plant, but 1.7% had bands from the pollen donor. The sexual offspring were all produced by mother plants of P. insularis , which is interpreted as a facultative apomict. Surprisingly, crosses between different taxa gave higher seed to ovule ratios and numbers of sexually produced offspring than crosses within taxa. Some of the sexually produced hybrid offspring had the same kind of hairs on the petioles as their mother taxon, showing that hybrids may not be intermediate in hair characters, which are considered important in the delimitation of these taxa. The results of the present study indicate very close relationships among the investigated plants.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 373−381.  相似文献   

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